I know, it’s 2017 and people are job hopping more than ever before. Most people will work for many more employers than people did in the 1950’s, but if you have a candidate who is 25 and has already had six jobs, that’s a red flag. It’s even more of a red flag if the candidate has held multiple jobs for less than one year. It indicates a lack of focus, poor decision-making skills and perhaps lack of competence. On its face, it also suggests that my company is not special and they are going to leave me too. So why should I bother to invest in that candidate? Work is work. It isn’t always fun, and you don’t want employees running at the earliest sign of difficulty. Employers want employees who can grind through the tough times and work through challenges and come out at the other end, all the better for it.

5. They Never Explained Why They Wanted The Role

I want to make sure that the candidate is a good fit for the position, not just the company. I always ask why the candidate wants this role. I want them to be excited about education, technology and being in a startup environment, but if they don’t mention anything related to the job that they will be doing, I’m concerned. I want the employee to want the job that we’re hiring for. Over time, it’s okay for employees to move around within a company and find other opportunities, but at the outset, you want to make sure their personality and interests match up with the current job description. This ensures they will be happy with their position for a decent amount of time.

Hiring is tough. If it were easy, no one would ever quit or get fired. Finding the right employee for the job requires much more than just a great resume. Of the many things that go into the hiring process, the personal interview is one of the most important tools in your toolkit. It gives you clues to what the candidate will be like as an employee and helps you identify personality and character traits that will be an asset or a hindrance in doing the job. Remember, a company is only as good as its weakest employee. Hire slow, fire fast and keep an eye out for these red flags.

Courtney Williams is the CEO and founder of Torsh. Follow him on Twitter and read the rest of his Forbes.com columns here.